L'utilisation d'algorithmes de vision permettrait d'élargir le domaine d'application des systèmes d'aide à la conduite à d'autres situations telles que : les scènes urbaines ou les conditions météorologiques dégradées. À cette fin, trois nouvelles applications sont étudiées dans cette thèse pour la pluie et les feux tricolores. La pluie est la condition météorologique dégradée la plus fréquente. Nous comparons les modèles physiques et photométriques existants pour la pluie et les gouttes de pluie. Lors d'une conduite en temps de pluie de jour, les gouttes sur le pare-brise diminuent considérablement la visibilité du conducteur. Lorsqu'elles sont vue par une camera embarquée standard celles-ci apparaissent défocalisées. Ainsi, nous proposons de détecter ces gouttes hors-focus en utilisant soit une approche par manque de gradients soit par l'évaluation locale du flou. Lors d'une conduite de nuit sous la pluie, ce sont les phares qui paradoxalement diminuent la visibilité car leur lumière est réfléchie par les gouttes vers le conducteur. Nous appuyant sur la conception d'un simulateur physique, nous proposons un éclairage adaptatif qui illuminerait la scène sans éclairer les gouttes qui tombent. Les résultats de notre simulateur et le premier prototype construit montre que l'idée avancée pourrait efficacement améliorer la visibilité générale d'une scène. D'autre part, nous étudions la détection et le suivi de gouttes de pluie à grande vitesse. Les feux tricolores ont un rôle crucial dans la compréhension des scènes urbaines. Bien qu'il existe déjà des systèmes de détection de feux tricolores, les algorithmes actuels ne fonctionnent que dans des conditions simples. Ainsi, nous avons développé un algorithme de détection de feux tricolores qui utilise une détection en niveau de gris des spots lumineux et une classification par reconnaissance de modèle. L'approche ainsi conçue est assez flexible pour détecter différents types de feux tricolores même avec une camera à faible dynamique. Notre proposition a été évaluée sur des séquences acquises en France, Chine et Suisse. / Vision algorithms can be used to expand the working range of the assistance systems so as to deal with urban scenes or degraded weathers. To this end, three novel applications are investigated in this thesis for both rain and traffic lights. Rain is the most frequent degraded weather condition. We review the various physics and photometry models for rain and raindrops, and highlight some of the misuses. When driving in daytime the raindrops on the windscreen lower the driver visibility. For standard on-board camera these drops appear as unfocused. Hence, we investigate the detection of unfocused raindrops using blur maps or lack of gradients with photometry. For nightime driving in rain, the headlights paradoxically reduce the visibility due to light reflected off of raindrops back toward the driver. Relying on a physic-based simulator, we propose to build an illumination device that would illuminate the scene without shining the falling particles. The performance of the simulator and a proof-of-concept prototype sustain that our idea can efficiently improve the overall scene visibility. Fast reactive drops detection and tracking is also investigated.To deal with urban scenes, traffic lights play a key role. Though traffic light recognition was attempted in the past, the existing algorithms can't handle complex scenarios. Hence, we have developed a traffic light recognition algorithm that uses a grayscale spot light detection and a template matching classification. Our approach is modular and capable of detecting various kind of traffic lights even when using a low-dynamic camera. We have evaluated our algorithm on sequences from France, China and Switzerland.

This paper addresses a design exploration focusing on interactive jewelry conducted with newcome LGBT+ immigrants in Sweden, leading to a necklace named PoWo that is “powered” by the spoken word through a mobile application that reacts to customizable keywords triggering LED-lights in the necklace. Interactive jewelry is in this paper viewed as a medium with a simultaneous relation to wearer and spectator thus affording use on the themes of symbolism, emotion, body and communication. These themes are demonstrated through specific use scenarios of the necklace relating to the participants of the design exploration e.g. addressing consent, societal issues, meeting situations and expressions of love and sexuality.  The potential of speech based interactive jewelry is investigated in this paper e.g. finding speech recognition in LED-jewelry to act as an amplifier of spoken words, actions and meaning; and as a visible extension of the smartphone and human body. In addition use qualities of visibility, ambiguity, continuity and fluency are discussed in relation to speech based LED-jewelry.

The master’s thesis deals with a solution of a complicated traffic situation on the Přímá – Nábřeží intersection in Zlin. The first part of the thesis focuses on the diagnostic of the current state of the junction. In the second part, the author compares possible solutions, traffic light control is chosen as the best. Traffic light plans are designed and coordinated with a nearby traffic light controlled intersection Tomáše Bati – Přímá. It the last part, the solution is verified and represented by a microsimulation.

La presente investigación analiza las condiciones de tráfico vehicular actual en dos intersecciones de la avenida Javier Prado Oeste, tramo Calle Las Flores & Calle Las Palmeras, en el distrito de San Isidro. La investigación empieza con la descripción de los problemas existentes en las intersecciones, como la deficiente programación de semáforos, falta de semáforos coordinados e incompatibilidad entre controladores semafóricos. El análisis de la investigación se realizó en base a un modelo microscópico, desarrollado con apoyo del software Vissim. El proceso de construcción de ambos modelos consiste en cuatro fases. La primera fase es el trabajo previo, en la cual se realizó la recolección de datos de campo. En segundo lugar, se encuentra la construcción de los modelos mediante el programa. En tercer lugar, se realizó la calibración y validación de ambos modelos en base a parámetros psicofísicos y estadísticos GEH para certificar que los resultados del modelo se asemejen a las condiciones actuales de las intersecciones. Por último, se incorporaron los nuevos flujos futuros en los modelos cada 15 minutos los cuales se simularon, evaluaron y compararon con los niveles de servicio obtenidos con las intersecciones proyectadas que incorporan la propuesta de mejora. Esencialmente los niveles de servicio de las intersecciones mejoran incorporando la propuesta de semáforos inteligente por medio de la optimización de ciclos semafóricos con el programa Synchro 10.0, esto se deduce a partir de la disminución de longitudes de colas en todos los accesos y la reducción de demoras de viaje en ambas intersecciones. / The present investigation analyzes the current vehicular traffic conditions at two intersections of Javier Prado Oeste Avenue, Las Flores Street and Las Palmeras Street, in the San Isidro district. The investigation begins with the description of the problems existing at the intersections, such as poor traffic light programming, lack of coordinated traffic lights and incompatibility between traffic light controllers. The research analysis was carried out based on a microscopic model, developed with the support of Vissim software. The construction process of both models consists of four phases. The first phase is the previous work, in which the field data collection was carried out. Second, there is the construction of the models through the program. Third, the calibration and validation of both models was performed based on GEH psychophysical and statistical parameters to certify that the results of the model resemble the current conditions of the intersections. Finally, the new future flows were incorporated into the models every 15 minutes, which were simulated, evaluated and compared with the service levels obtained with the projected intersections that incorporate the improvement proposal. Essentially, the service levels of the intersections improve by incorporating the smart traffic lights proposal through the optimization of traffic light cycles with the Synchro 10.0 program, this is deduced from the decrease in queue lengths in all accesses and the reduction of delays of travel at both intersections. / Tesis

The lighting retrofit method is adopted as one of the solutions to reduce lighting energy consumption and improve lighting quality in existing buildings. Lighting controls and energy-efficient light sources are used to achieve the goals of the lighting retrofit. Nowadays, Light-Emitting Diodes (LEDs) are replacing traditional lighting technology owing to their high efficiency and longevity. One of the advantages of LEDs is the controllability function, which allows users to set the light level according to their preferences. This saves more energy and satisfies users’ lighting needs. However, over time, the performance of lighting retrofit projects deteriorates subject to failure of the retrofitted lights. Therefore, to maintain the performance of lighting retrofit projects, maintenance must be planned and performed. The impacts of the users’ lighting level requirements on LEDs’ life characteristics and lighting system performance are investigated by using lighting controls. Light and occupancy sensors adjust artificial light to the light level required by users and detect the presence of users in the zones, respectively. Light sensors measure the average illuminance in the zones. The measured illuminance is compared to the users’ set illuminance; if the measured illuminance is higher than the users’ set illuminance, lamps are dimmed to meet users’ lighting preference, when the measured illuminance is less than the users’ set illuminance, lamps in the zone are replaced by new ones. The dimming level in each zone at each sampling interval is used to estimate the operating junction temperature, thereafter the degradation rate and luminous flux are calculated. Light levels at workspace are modelled using the lumen method. This model helps to quantify energy savings and predict when lamps will fail to deliver the required light levels. In existing studies, users’ lighting level requirements are neglected when investigating the lifetime of the lighting system; however, users’ profile and driving schemes affect the operating conditions of a lighting system. From the simulation results, it is noted that lumen output degradation increases when the user’s set illuminance is above the illuminance required under normal operating conditions and decreases when the user’s set illuminance is below the illuminance required under normal operating conditions. Increased lumen output degradation shortens the lifetime of LEDs and reduces energy savings, while decreased lumen output degradation extends the lifetime and increases energy savings. Generally, lighting retrofit projects contain a large lighting population; investigating when each lamp will fail can be time-consuming and costly. In this research, a mathematical model is formulated to model LEDs’ failure by analysing the statistical properties of the lumen degradation rates. Based on the statistical properties of the degradation rates, the cumulative probability of failure distribution and the survival function are modelled. The formulated survival function is incorporated into the lighting maintenance optimization problem to balance energy savings and maintenance costs. A case study carried out shows that, in 10 years, the optimal lighting maintenance plan would save up to 59% of lighting energy consumption with acceptable maintenance costs. It is found that the proposed maintenance plan is more cost-effective than full maintenance. It is concluded that lumen degradation failure should be considered when investigating the performance of lighting retrofit projects, as this may not only affect energy savings but also reduce the level of illumination, which can cause visual discomfort. The initial investment costs of LEDs are still a barrier to the implementation of LED lighting systems in residential buildings. Energy-efficiency projects often face hurdles to access capital investments because decision-makers and funders do not have enough information about operational savings the project can provide and specific financial requirements applied to efficiency investment. In this research, an optimization model is formulated to give decision-makers and funders detailed information about the performance and operational savings that a LED lighting retrofit project can offer and its economic viability. The lumen degradation failure model developed is used to monitor and estimate the energy savings, and the optimal maintenance plan is scheduled to replace failed lamps. In the existing studies, the economic analysis of the lighting retrofit projects is assessed based on lighting population decay due to burnout failure while in this research economic analysis is assessed by considering the lumen degradation failure. The case study results show that the substitution of halogen light bulbs with LED light bulbs could save up to 291.4 GWh of energy consumption, and reduce 273:92 103 tons of CO2 emissions over 10-year period. The optimization model formulated is effective to help the decision-makers and funders to quantify the savings and assess the economic viability of the LED lighting retroïnˇA˛t project. This optimization model can help the decision-makers and funders to make an informed decision. / Thesis (PhD (Electrical Engineering))--University of Pretoria, 2020. / Electrical, Electronic and Computer Engineering / PhD (Electrical Engineering) / Unrestricted

The nighttime distribution of vertically migrating mesopelagic fish in relation to nocturnal light was studied during a circumglobal survey, in the Red Sea, and in a fjord at high latitude. The study was based on data derived from ship borne echo sounders (circumglobal and the Red Sea) as well as using upward looking echo sounders mounted on the bottom (Masfjorden, Norway). We also applied a numerical model for analyzing diel vertical migration patterns. The effect of the lunar cycle was the focus in studies at low latitudes, while seasonal changes in nocturnal light climate was in focus at high latitude. Lunar phase significantly affected the distribution of mesopelagic fish at the global scale and in the Red Sea. During nights near full moon, scattering layers of mesopelagic fish distributed deeper than during darker phases of the moon. At high latitude, mesopelagic fish switched its behavior along with seasonal changes in nocturnal lights. In autumn, the population of the studied fish (Maurolicus mueleri) formed separated layers. Juveniles performed normal diel vertical migration followed by midnight sinking, with midnight sinking mainly related to temperature minima and also for avoiding predators. Meanwhile the adults did not migrate vertically, reducing foraging but increasing the adult survival. From late winter to mid-Spring, interrupted ascents behavior was noted in the afternoon. Predator avoidance, satiation, and finding temperature optimum might be the reason behind interrupted ascents. At lighter nights in mid-summer, M. muelleri took on schooling behavior, likely as an anti-predator behavior permitting access to the upper waters in the absence of darkness.

Una manera de evaluar si las soluciones para intersecciones urbanizadas son sostenibles en el tiempo, es calculando las demoras para un tránsito futuro y la presente investigación determina la precisión de dicha evaluación. La demora vehicular es uno de los parámetros más importantes utilizado para evaluar el rendimiento de las intersecciones semaforizadas, por tal motivo, profesionales del transporte usan como criterio de optimización del tráfico, la disminución de las demoras. En este artículo, se presenta un enfoque para evaluar la precisión del método de sostenibilidad en el tiempo para intersecciones urbanas, para lo cual se analizarán las demoras en una intersección para diferentes escenarios. Primero, se modelará la intersección de estudio mediante el software Synchro 10. En segundo lugar, el modelo se aplicará para diversos escenarios donde el volumen vehicular incrementará dependiendo del crecimiento vehicular. Se demuestra que, a partir de las demoras obtenidas para cada escenario, se puede estimar la precisión de aplicar la solución que se desee en una intersección, esto en base a la tendencia de la curva de variación porcentual de las demoras en el tiempo. En resumen, la metodología puede ser aplicada en diferentes intersecciones urbanizadas y escenarios donde se pretenda plantear soluciones que sean sostenibles en el tiempo. / A way to evaluate if the solutions for urban intersections are sustainable in time, is about calculating the delays for a future traffic and the present investigation establishes the accuracy of that evaluation. The vehicular delay is one of the most important parameters that is used to evaluate the performance of traffic light intersections, for this reason, professionals of transport use as traffic optimization judgment the decrease of delays. This article presents an approach to evaluate the accuracy for the sustainability method in time for urban intersections, for which this investigation analyzes the delays in one intersection for different stages. This project begins with a model of the intersection of study helped by the software Synchro 10. Then, the model will be applied for many stages where the vehicular volume will be increased depending the vehicular growth. Finally, it is proved that due to the estimated delays for each stage, it will be possible to estimate the accuracy of applying a desired solution in an intersection, that is based on the trend of percentages variation curve on time delays. In brief, the methodology could be applied in different urban intersections and stages where it is pretended to propose solutions that are sustainable over the time. / Trabajo de investigación

With increasing popularity of indoor farming, more and more home growers are faced with sub-optimal lighting conditions in northern countries or poorly lit windows. We have designed and built a proof-of-concept system capable of reducing electricity cost and CO2 footprint of the electricity used for consumer grade grow lights without adversely impacting the grow cycle of the plant. Our system provides optimal grow light conditions for a given plant while using forecasts and live grid data from the ENTSO-E transparency platform to automatically use or store electricity during low-cost hours and avoid using grid electricity during high-cost hours, but can also be configured to prioritize electricity use when the available grid power’s carbon intensity is low. The system, consisting of a server and an embedded control unit, was designed and implemented according to Nunamaker and Chen’s five-step iterative systems development research method and later evaluated by simulating the system for 14 days using real world sunlight and grid data. The results of the simulation show a significant reduction in both spending and carbon emissions related to electricity use, with figures of 73% and 28%, respectively. However, when accounting for life-cycle cost and emissions from the battery, the prototype in its current configuration is neither profitable nor a net positive for the environment. With changes to battery type and taking advantage of economies of scale, a future version could be economically viable, but to be environmentally sustainable, further advances in eco-friendly battery production are needed.

Indiana University-Purdue University Indianapolis (IUPUI) / Objective: The objective was to assess a multiple emission peak light-emitting-diode (LED) light-curing unit (LCU) by measuring the polymerization efficiency through the degree of conversion (DC) and Knoop microhardness (KHN) of a resin-based pit and fissure sealant at various light curing times and two distances compared to a single emission peak LED LCU. Method: Sixty disks of resin-based pit and fissure sealant (Delton, DENTSPLY, York, PA) samples (6x1mm) were fabricated (n=5/LCU/group). Prepared samples were polymerized using 10, 20 and 40 second curing time at 2 or 4 mm curing distances. The irradiance and radiant exposure received on the top/bottom surfaces of the samples were measured using the Managing Accurate Resin Curing-Resin Calibrator (MARC-RC) system. The samples were stored at 37°C for one hour. Then, the DC (n=3/surface) and KHN (n=5/surface) measurements were collected on the top and bottom surfaces using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and a microhardness tester (Instron) utilizing 25-gm at 10 seconds dwell time, respectively. Multiple-way ANOVA was performed followed by Tukey test (α=0.05). Result: The irradiance from the multiple emission peak LED LCU was significantly higher than the single emission peak LED LCU (1312.6 and 768.3 mW/cm2) respectively. Moreover, the multiple emission peak LED LCU displayed significantly higher DC (82.5%) and microhardness (26.2 KHN) compared to the single emission peak LED LCU (75.5% DC and 21.2 KHN) when curing samples at 2 and 4 mm curing distances assessed using 10, 20 and 40-second curing times. The 10 second cure at 4 mm showed significantly lower DC and KHN values compared to the other groups. Conclusion: The multiple emission peak LED LCU demonstrated significantly higher irradiance, DC and KHN compared to the single emission peak LED LCU on a resin-based pit and fissure sealant at 2 and 4 mm curing distances and 10, 20 and 40 second curing times. Therefore, the multiple emission peak LED LCU performed higher than the single emission peak LED LCU.

Indiana University-Purdue University Indianapolis (IUPUI) / Background. Beam profile non-uniformity of light-curing units (LCUs) may result in suboptimal properties of resin-matrix composite (RMC) restorations. Objectives: The objective of this study was to evaluate the effect of curing-light beam profile of multiple light curing units (LCUs) on the degree of conversion (DC) and micro-flexural strength (μ-flexural strength) of RMC. Methods: Forty-five nano-filled hybrid RMC (Tetric EvoCeram, Ivoclar Vivadent, Amherst, NY) specimens were fabricated. Quartz tungsten halogen (QTH) (Optilux 401) (O), multiple emission peak (VALO Cordless) (V) and single emission peak (Demi Ultra) (DU) light-emitting-diode (LED) LCUs were investigated at different light-curing locations (LCLs): 1) the center of the LCU tip; 2) 1.5 mm to the left of the center of the LCU tip; and 3) 1.5 mm to the right of the center of the LCU tip. Specimens were stored wet in deionized water at 37C for 24 hours. The DC was measured on top and bottom surfaces using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. Micro-flexural strength testing was performed using a universal mechanical testing machine at crosshead speed of 1 mm/min. Multi-factorial ANOVAs were used to analyze the data (α = 0.05). Results: All LCUs exhibited significant differences in DC between top and bottom surfaces at the different LCLs. Micro-flexural strength varied with LCL for DU. Conclusions: The non-uniform curing-light beam profile could have a significant effect on μ-flexural strength and DC on top and bottom surfaces of RMC specimens cured at different LCLs.